Flexible Endoscopic Catheter with Ligasure

ABSTRACT

An endoscopic forceps is disclosed including an end effector assembly having two jaw members movable from a first position in spaced relation relative to one another to at least a second position closer to one another for grasping tissue therebetween. Each of the jaw members is connectable to an electrosurgical energy source for conducting energy through tissue held therebetween. The jaw members are biased to the first position. The end effector assembly of the endoscopic forceps further includes a wire snare having a proximal end connectable to an electrosurgical energy source and a distal end translatably extending out of one of the jaw members and operatively associated with the other of the jaw members. In use, withdrawal of the proximal end of the wire snare results in movement of the jaw members from the first position to a second position and clamping of the tissue between the jaws.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Divisional Application that claims the benefit ofand priority to U.S. application Ser. No. 11/540,779, filed on Sept. 29,2006, which claims the benefit of and priority to each of U.S.Provisional Application No. 60/722,359, filed on Sept. 30, 2005; U.S.Provisional Application No. 60/722,213, filed on Sept. 30, 2005; andU.S. Provisional Application No. 60/722,186, filed on Sept. 30, 2005,the entire contents of each application being incorporated by referenceherein.

BACKGROUND

1. Technical Field

The present disclosure relates to electrosurgical instruments and, moreparticularly, to flexible endoscopic bipolar electrosurgical forceps forsealing and/or cutting tissue.

2. Discussion of Related Art

Electrosurgical forceps utilize both mechanical clamping action andelectrical energy to affect hemostasis by heating the tissue and bloodvessels to coagulate, cauterize and/or seal tissue. As an alternative toopen forceps for use with open surgical procedures, many modern surgeonsuse endoscopes and endoscopic instruments for remotely accessing organsthrough smaller, puncture-like incisions. As a direct result thereof,patients tend to benefit from less scarring and reduced healing time.

Many surgical procedures may be completed through intra-luminaltechniques, where a flexible endoscope is accessed through a punctureinto a vascular branch or through one end of the gastrointestinal tract(e.g., the mouth or the rectum). These flexible endoscopes may containlumens for purposes of irrigation, suction or passage or surgicalinstruments (e.g., snares, organ catheters, biopsy devices, etc.).

Many other surgical procedures utilize endoscopic instruments which areoften inserted into the patient through a cannula, or port, which hasbeen made with a trocar. Typical sizes for cannulas range from threemillimeters to twelve millimeters. Smaller cannulas are usuallypreferred, which, as can be appreciated, ultimately presents a designchallenge to instrument manufacturers who attempt to find ways to makeendoscopic instruments that fit through the smaller cannulas.

Many endoscopic surgical procedures require cutting or ligating bloodvessels or vascular tissue. Due to the inherent spatial considerationsand accessibility of the indoluminal sight, surgeons often havedifficulty suturing vessels or performing other traditional methods ofcontrolling bleeding, e.g., clamping and/or tying-off transected bloodvessels. By utilizing an endoscopic electrosurgical forceps, a surgeoncan either cauterize, coagulate/desiccate and/or simply reduce or slowbleeding simply by controlling the intensity, frequency and duration ofthe electrosurgical energy applied through the jaw members to thetissue. Most small blood vessels, i.e., in the range below twomillimeters in diameter, can often be closed using standardelectrosurgical instruments and techniques. However, if a larger vesselis ligated, it may be necessary for the surgeon to convert theendoscopic procedure into an open-surgical procedure and thereby abandonthe benefits of endoscopic surgery. Alternatively, the surgeon can sealthe larger vessel or tissue.

It is thought that the process of coagulating vessels is fundamentallydifferent than electrosurgical vessel sealing. For the purposes herein,“coagulation” is defined as a process of desiccating tissue wherein thetissue cells are ruptured and dried. “Vessel sealing” or “tissuesealing” is defined as the process of liquefying the collagen in thetissue so that it reforms into a fused mass. Coagulation of smallvessels is sufficient to permanently close them, while larger vesselsneed to be sealed to assure permanent closure.

In order to effectively seal larger vessels (or tissue) two predominantmechanical parameters are accurately controlled—the pressure applied tothe vessel (tissue) and the gap distance between the electrodes—both ofwhich are affected by the thickness of the sealed vessel. Moreparticularly, accurate application of pressure is important to opposethe walls of the vessel; to reduce the tissue impedance to a low enoughvalue that allows enough electrosurgical energy through the tissue; toovercome the forces of expansion during tissue heating; and tocontribute to the end tissue thickness which is an indication of a goodseal. It has been determined that a typical fused vessel wall is optimumbetween 0.001 and 0.006 inches. Below this range, the seal may shred ortear and above this range the lumens may not be properly or effectivelysealed.

With respect to smaller vessels, the pressure applied to the tissuetends to become less relevant whereas the gap distance between theelectrically conductive surfaces becomes more significant for effectivesealing. In other words, the chances of the two electrically conductivesurfaces touching during activation increases as vessels become smaller.

As mentioned above, in order to properly and effectively seal largervessels or tissue, a greater closure force between opposing jaw membersis required. It is known that a large closure force between the jawstypically requires a large moment about the pivot for each jaw. Thispresents a design challenge because the jaw members are typicallyaffixed with pins which are positioned to have small moment arms withrespect to the pivot of each jaw member. A large force, coupled with asmall moment arm, is undesirable because the large forces may shear thepins. As a result, designers compensate for these large closure forcesby either designing instruments with metal pins and/or by designinginstruments which at least partially offload these closure forces toreduce the chances of mechanical failure. As can be appreciated, ifmetal pivot pins are employed, the metal pins should be insulated toavoid the pin acting as an alternate current path between the jawmembers which may prove detrimental to effective sealing.

Increasing the closure forces between electrodes may have otherundesirable effects, e.g., it may cause the opposing electrodes to comeinto close contact with one another which may result in a short circuitand a small closure force may cause pre-mature movement of the tissueduring compression and prior to activation. As a result thereof,providing an instrument which consistently provides the appropriateclosure force between opposing electrode within a preferred pressurerange will enhance the chances of a successful seal. As can beappreciated, relying on a surgeon to manually provide the appropriateclosure force within the appropriate range on a consistent basis wouldbe difficult and the resultant effectiveness and quality of the seal mayvary. Moreover, the overall success of creating an effective tissue sealis greatly reliant upon the user's expertise, vision, dexterity, andexperience in judging the appropriate closure force to uniformly,consistently and effectively seal the vessel. In other words, thesuccess of the seal would greatly depend upon the ultimate skill of thesurgeon rather than the efficiency of the instrument.

It has been found that the pressure range for assuring a consistent andeffective seal is between about 3 kg/cm2 to about 16 kg/cm2 and,desirably, within a working range of 7 kg/cm2 to 13 kg/cm2.Manufacturing an instrument which is capable of providing a closurepressure within this working range has been shown to be effective forsealing arteries, tissues and other vascular bundles.

Various force-actuating assemblies have been developed in the past forproviding the appropriate closure forces to affect vessel sealing. Forexample, one such actuating assembly has been developed by Valleylab,Inc. of Boulder, CO, a division of Tyco Healthcare LP, for use withValleylab's vessel sealing and dividing instrument commonly sold underthe trademark LIGASURE ATLAS®. This assembly includes a four-barmechanical linkage, a spring and a drive assembly which cooperate toconsistently provide and maintain tissue pressures within the aboveworking ranges. The LIGASURE ATLAS® is presently designed to fit througha 10 mm cannula and includes a bilateral jaw closure mechanism which isactivated by a foot switch. A trigger assembly extends a knife distallyto separate the tissue along the tissue seal. A rotating mechanism isassociated with distal end of the handle to allow a surgeon toselectively rotate the jaw members to facilitate grasping tissue.Co-pending U.S. application Ser. Nos. 10/179,863 and 10/116,944 and PCTApplication Serial Nos. PCT/US01/01890 and PCT/7201/11340 describe indetail the operating features of the LIGASURE ATLAS® and various methodsrelating thereto. The contents of all of these applications are herebyincorporated by reference herein.

Electrosurgical snares are used in endoscopic electrosurgical proceduresof the removal of intestinal polyps and the like. Electrosurgical snaresare predominantly monopolar, are used typically without any feedback tothe electrosurgical generator, and typically lack control over theamount of cauterization of tissue. During a poly removal procedure,power applied to a stem of the polyp must be carried away through thewall of the underlying tissue (i.e., intestinal wall or other bodylumen).

It would be desirous to develop an endoscopic vessel sealing instrumentwhich reduces the overall amount of mechanical force necessary to closethe jaw members and to clamp tissue therebetween. It would also bedesirous for the instrument to provide a variable-ratio mechanicaladvantage for manipulating the jaw members and clamping tissue, suchthat, for example, the jaw members can be closed on tissue, easier,quicker and with less user force than previously envisioned to clamp thetissue.

Additionally, it would be desirous for the instrument to include a bladefor cutting tissue following electrosurgical sealing.

Additionally, it would be desirous for the instrument to be a bipolarinstrument capable of reducing or limiting the effect to tissue capturedbetween the jaw members.

Additionally, one must consider the ability to manipulate the positionof the surgical end effector. Controls are available to bend theflexible endoscope to position the view angle and the ports relative tothe surgical target. It is then additionally desirable to manipulate thesurgical effector within the view field of the endoscope. This may beaccomplished by any number of means, such as, for example, pull wires,thermally active memory wire, or micro-machines.

SUMMARY

The present disclosure relates to flexible endoscopic bipolarelectrosurgical forceps for sealing and/or cutting tissue.

According to an aspect of the present disclosure, an endoscopic forcepsfor vessel sealing is provided. The endoscopic forceps includes ahousing; a shaft extending from the housing and including a distal endconfigured and adapted to support an end effector assembly; and an endeffector assembly operatively supported on the distal end of the shaft.

The end effector assembly includes two jaw members movable from a firstposition in spaced relation relative to one another to at least a secondposition closer to one another for grasping tissue therebetween. Each ofthe jaw members is adapted to connect to an electrosurgical energysource such that the jaw members are capable of conducting energythrough tissue held therebetween to affect a tissue seal. The endeffector assembly further includes an outer sleeve translatably disposedabout the shaft. The sleeve has a first position in which the sleevedoes not cover the jaw members, and a plurality of second positions inwhich the sleeve covers at least a portion of the two jaws toapproximate the jaws at least partially toward one another. The endeffector assembly includes a linkage operatively connected to at leastone of the jaw members for pivoting both jaw members about a commonpivot axis.

The endoscopic forceps includes a movable handle operatively associatedwith the housing. Accordingly, actuation of the movable handle relativeto the housing results in movement of the outer sleeve relative the jawmembers to actuate the end effector assembly between the first andsecond positions.

The jaw members may be biased to the first position. The jaw members areeither unilateral or bilateral. The end effector assembly includes atleast one stop member disposed on an inner facing surface of at leastone of the jaw members. The end effector assembly may deliver a workingpressure of about 3 kg/cm² to about 16 kg/cm², preferably of about 7kg/cm² to about 13 kg/cm².

In an embodiment, the jaw members are pivotable to a substantiallyorthogonal orientation relative to a longitudinal axis of the shaft. Thelinkage desirably actuates the jaw members from the first position to asecond position. The linkage may be operatively connected to one of thejaw members.

The shaft and outer sleeve may be at least partially flexible.

According to another aspect of the present disclosure, the endoscopicforceps includes a housing; a shaft extending from the housing andincluding a distal end configured and adapted to support an end effectorassembly; and an end effector assembly operatively supported on thedistal end of the shaft. The end effector assembly includes two jawmembers movable from a first position in spaced relation relative to oneanother to at least a second position closer to one another for graspingtissue therebetween. Each of the jaw members is adapted to connect to anelectrosurgical energy source such that the jaw members are capable ofconducting energy through tissue held therebetween to affect a tissueseal. The jaw members are biased to the first position. The end effectorassembly of the endoscopic forceps further includes a wire having aproximal end connectable to an electrosurgical energy source and adistal end translatably extending out of one of the jaw members andoperatively associated with the other of the jaw members. Accordingly,in use, withdrawal of the proximal end of the wire results in movementof the jaw members from the first position to a second position andcinching of the wire onto and/or around the tissue.

The jaw members may be unilateral or bilateral.

The distal end of the wire may translatably extend through the other ofthe jaw members and may be secured to itself. The wire may be fabricatedfrom shape-memory alloys.

It is envisioned that at least a portion of the shaft is flexible. In anembodiment, a distal most end of the shaft is rigid.

The end effector assembly may further include a scissor bladeoperatively supported on a distal end of the shaft and movable from afirst position in which the scissor blade is substantially aligned withone of said jaw members and a plurality of second positions in which thescissor blade is out of alignment with the one jaw member and extendsacross to the other of the jaw members thereby severing tissue graspedbetween the jaw members.

In an embodiment, the end effector assembly may still further include ascissor blade linkage operatively connected to the scissor blade.Accordingly, in use, movement of the scissor linkage results inactuation of the scissor blade between the first position and any numberof second positions.

According to still a further aspect of the present disclosure, theendoscopic forceps includes a housing; a shaft extending from thehousing and including a distal end configured and adapted to support anend effector assembly; and an end effector assembly operativelysupported on the distal end of the shaft. The end effector assemblyincludes a cutting blade supported on the distal end of the shaft, thecutting blade including a cutting edge extending in a distal direction;a movable jaw member translatably supported on the shaft, the movablejaw member including a tissue contacting portion extending across alongitudinal axis of the shaft; and an anvil member slidably supportedon the movable jaw member between the tissue contacting portion of themovable jaw member and the cutting blade, the anvil member defining ablade slot formed therein for selectively receiving the cutting bladetherethrough. The endoscopic forceps further includes a movable handleoperatively associated with the housing, wherein actuation of themovable handle relative to the housing results in movement of themovable jaw member relative to the shaft.

The end effector assembly may further include a biasing member disposedbetween the anvil member and the cutting blade for maintaining the anvilmember biased a distance away from the cutting blade such that thecutting blade does not extend through the anvil member.

The end effector assembly may include a first position wherein thetissue contacting portion of the movable jaw member is spaced a distancefrom the anvil member for receiving a target tissue therein, and theanvil member is spaced a distance from the cutting blade such that thecutting blade does not extend through the blade slot formed therein. Theend effector assembly may further include a second position wherein thetissue contacting portion of the movable jaw member is approximatedtoward the anvil member to grasp the tissue therebetween, and the anvilmember is spaced a distance from the cutting blade such that the cuttingblade does not extend through the blade slot formed therein. The endeffector assembly may include a third position wherein the tissuecontacting portion of the movable jaw member is approximated toward theanvil member to grasp the tissue therebetween, and the anvil member isapproximated toward the cutting blade such that the cutting edge of thecutting blade extends through the blade slot formed therein severs thetissue extending thereacross.

For a better understanding of the present disclosure and to show how itmay be carried into effect, reference will now be made by way of exampleto the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the subject instrument are described herein withreference to the drawings wherein:

FIG. 1 is a perspective view of an endoscopic bipolar forceps showing ahousing, a shaft and an end effector assembly according to the presentdisclosure;

FIG. 2 is an enlarged perspective view of the end effector assembly ofFIG. 1, with the jaw members in an open configuration;

FIG. 3 is a schematic, side elevational view of an end effectoraccording to an embodiment of the present disclosure, with the jawmembers in an open configuration;

FIG. 4 is a schematic, side elevational view of the end effector of FIG.3 with the jaw members in a closed configuration;

FIG. 5 is a schematic, side elevational view of an end effectoraccording to another embodiment of the present disclosure, in a firstclosed configuration;

FIG. 6 is a schematic, side elevational view of the end effector of FIG.5, in a second closed configuration for transmitting clamping force totissue interposed therebetween;

FIG. 7 is a schematic, side elevational view of an end effectoraccording to yet another embodiment of the present disclosure, with thejaw members in an open configuration;

FIG. 8 is a schematic, side elevational view of the end effector of FIG.7 with the jaw members in a closed configuration;

FIG. 9 is a schematic, side elevational view of an end effectoraccording to still another embodiment of the present disclosure, withthe jaw members in an open configuration;

FIG. 10 is a schematic, side elevational view of the end effector ofFIG. 9 with the jaw members in a closed configuration;

FIG. 11 is a schematic, side elevational view of an end effectoraccording to another embodiment of the present disclosure, with the jawmembers in an open configuration;

FIG. 12 is a schematic, side elevational view of the end effector ofFIG. 11 with the jaw members in a closed configuration;

FIG. 13 is a schematic, side elevational view of an end effectoraccording to yet another embodiment of the present disclosure,illustrating a scissor blade in an unactuated condition;

FIG. 14 is a schematic, distal end view of the end effector of FIG. 13,including tissue interposed between the jaw members;

FIG. 15 is a schematic, side elevational view of the end effector ofFIGS. 13 and 14, illustrating the scissor blade in an actuatedcondition;

FIG. 16 is a schematic, distal end view of the end effector of FIG. 15;

FIG. 17 is a schematic, top plan view of the end effector of FIGS.13-16;

FIG. 18 is a schematic, perspective view of an end effector according toyet another embodiment of the present disclosure, shown in a firstcondition;

FIG. 19 is a schematic, perspective view of the end effector of FIG. 18,shown in a second condition; and

FIG. 20 is a schematic, perspective view of the end effector of FIGS. 18and 19, shown in a third condition.

DETAILED DESCRIPTION

Turning now to FIGS. 1 and 2, an embodiment of an endoscopic bipolarforceps 10 is shown for use with various surgical procedures andgenerally includes a housing 20, a handle assembly 30, a rotatingassembly 80, a trigger assembly 70 and an end effector assembly 100 thatoperates to grasp, seal, divide, cut and dissect corporal tissue and thelike. Although the majority of the figure drawings depict a bipolarforceps 10 for use in connection with endoscopic surgical procedures,the present disclosure may be used for more traditional open surgicalprocedures. For the purposes herein, the forceps 10 is described interms of an endoscopic instrument, however, it is contemplated that anopen version of the forceps may also include the same or similaroperating components and features as described below.

In the drawings and in the descriptions that follow, the term“proximal,” as is traditional, will refer to the end of the forceps 10which is closer to the user, while the term “distal” will refer to theend that is farther from the user.

Forceps 10 includes a shaft 12 that has a distal end 16 dimensioned tomechanically engage end effector assembly 100 and a proximal end 14 thatmechanically engages the housing 20. Proximal end 14 of shaft 12 isreceived within housing 20 and appropriate mechanical and electricalconnections relating thereto are established.

As best seen in FIG. 1, forceps 10 also includes an electrosurgicalcable 310 that connects the forceps 10 to a source of electrosurgicalenergy, e.g., a generator (not shown). It is contemplated thatgenerators such as those sold by Valleylab—a division of Tyco HealthcareLP, located in Boulder CO are used as a source of electrosurgicalenergy, e.g., FORCE EZ™ Electrosurgical Generator, FORCE FX™Electrosurgical Generator, FORCE 1C™, FORCE 2™ Generator, SurgiStat™ II.One such system is described in commonly-owned U.S. Pat. No. 6,033,399entitled “ELECTROSURGICAL GENERATOR WITH ADAPTIVE POWER CONTROL” theentire contents of which are hereby incorporated by reference herein.Other systems have been described in commonly-owned U.S. Pat. No.6,187,003 entitled “BIPOLAR ELECTROSURGICAL INSTRUMENT FOR SEALINGVESSELS” the entire contents of which are also incorporated by referenceherein.

In one embodiment, the generator includes various safety and performancefeatures including isolated output, independent activation ofaccessories. It is envisioned that the electrosurgical generatorincludes Valleylab's Instant Response™ technology features that providesan advanced feedback system to sense changes in tissue 200 times persecond and adjust voltage and current to maintain appropriate power. TheInstant Response™ technology is believed to provide one or more of thefollowing benefits to surgical procedure:

Consistent clinical effect through all tissue types;

Reduced thermal spread and risk of collateral tissue damage;

Less need to “turn up the generator”; and

Designed for the minimally invasive environment.

Cable 310 is internally divided into several cable leads (not shown)which each transmit electrosurgical energy through their respective feedpaths through the forceps 10 to the end effector assembly 100.

Handle assembly 30 includes a fixed handle 50 and a movable handle 40.Fixed handle 50 is integrally associated with housing 20 and handle 40is movable relative to fixed handle 50. In one embodiment, rotatingassembly 80 is integrally associated with housing 20 and is rotatableapproximately 180 degrees about a longitudinal axis.

As mentioned above, end effector assembly 100 is attached at distal end16 of shaft 12 and includes a pair of opposing jaw members 110 and 120.Movable handle 40 of handle assembly 30 is ultimately connected to adrive assembly (not shown) which, together, mechanically cooperate toimpart movement of jaw members 110 and 120 from an open position whereinjaw members 110 and 120 are disposed in spaced relation relative to oneanother, to a clamping or closed position wherein jaw members 110 and120 cooperate to grasp tissue therebetween.

It is envisioned that forceps 10 may be designed such that it is fullyor partially disposable depending upon a particular purpose or toachieve a particular result. For example, end effector assembly 100 maybe selectively and releasably engageable with distal end 16 of the shaft12 and/or the proximal end 14 of shaft 12 may be selectively andreleasably engageable with the housing 20 and the handle assembly 30. Ineither of these two instances, the forceps 10 would be considered“partially disposable” or “reposable”, i.e., a new or different endeffector assembly 100 (or end effector assembly 100 and shaft 12)selectively replaces the old end effector assembly 100 as needed. As canbe appreciated, the presently disclosed electrical connections wouldhave to be altered to modify the instrument to a reposable forceps.

As shown best in FIG. 2, end effector assembly 100 includes opposing jawmembers 110 and 120 that cooperate to effectively grasp tissue foroperative purposes. End effector assembly 100 may be designed as aunilateral assembly, i.e., jaw member 120 is fixed relative to the shaft12 and jaw member 110 pivots about a pivot pin 103 to grasp tissue andthe like or as a bilateral assembly, i.e., both jaw members pivotrelative to one another.

More particularly, and with respect to the particular embodiments shownin FIG. 2, the unilateral end effector assembly 100 includes onestationary or fixed jaw member 120 mounted in fixed relation to shaft 12and pivoting jaw member 110 mounted about a pivot pin 103 attached tothe stationary jaw member 120. A reciprocating sleeve 60 is slidinglydisposed within the shaft 12 and is remotely operable by a driveassembly. The pivoting jaw member 110 includes a detent or protrusion117 that extends from jaw member 110 through an aperture (not shown)disposed within the reciprocating sleeve 60. Pivoting jaw member 110 isactuated by sliding the sleeve 60 axially within shaft 12 such that adistal end of the aperture abuts against detent 117 on pivoting jawmember 110. Pulling sleeve 60 proximally closes jaw members 110 and 120about tissue and the like, and pushing sleeve 60 distally opens jawmembers 110 and 120.

As illustrated in FIG. 2, a knife channel 115 b runs through the centerof the jaw member 120 (a complementary knife channel is formed in jawmember 110) such that a blade from a knife assembly (not shown) may cutthrough the tissue grasped between jaw members 110 and 120 when jawmembers 110 and 120 are in a closed position. Details relating to theknife channel 115 and the knife actuating assembly including triggerassembly 70 are explained in limited detail herein and explained in moredetail with respect to commonly-owned U.S. patent application Ser. Nos.10/460,926, filed Jun. 13, 2003 and 10/953,757, filed Sept. 29, 2004,the entire contents of which are both incorporated by reference herein.

With continued reference to FIG. 2, jaw member 110 also includes a jawhousing 116 Ser. No. 10/953,757 has an insulative substrate or insulator114 and an electrically conducive sealing surface 112. In oneembodiment, insulator 114 is dimensioned to securely engage theelectrically conductive sealing surface 112. This may be accomplished bystamping, by overmolding, by overmolding a stamped electricallyconductive sealing plate and/or by overmolding a metal injection moldedseal plate. Movable jaw member 110 also includes a wire channel 113 Ser.No. 10/953,757 is designed to guide a cable lead 311 into electricalcontinuity with electrically conducive sealing surface 112 as describedin more detail below.

Desirably, jaw member 110 has an electrically conducive sealing surface112 which is substantially surrounded by an insulating substrate 114.Insulating substrate 114, electrically conductive sealing surface 112and the outer, non-conductive jaw housing 116 can be dimensioned tolimit and/or reduce many of the known undesirable effects related totissue sealing, e.g., flashover, thermal spread and stray currentdissipation. Alternatively, it is envisioned that jaw members 110 and120 may be manufactured from a ceramic-like material and theelectrically conducive sealing surface(s) 112 thereof may be coated ontothe ceramic-like jaw members 110 and 120.

It is envisioned that the electrically conductive sealing surface 112may also include an outer peripheral edge that has a pre-defined radiusand the insulating substrate 114 meets the electrically conductivesealing surface 112 along an adjoining edge of the sealing surface 112in a generally tangential position. In one embodiment, at the interface,the electrically conducive sealing surface 112 is raised relative to theinsulating substrate 114. These and other envisioned embodiments arediscussed in co-pending, commonly assigned Application Serial No.PCT/US01/11412 entitled “ELECTROSURGICAL INSTRUMENT WHICH REDUCESCOLLATERAL DAMAGE TO ADJACENT TISSUE” by Johnson et al. and co-pending,commonly assigned Application Serial No. PCT/US01/11411 entitled“ELECTROSURGICAL INSTRUMENT WHICH IS DESIGNED TO REDUCE THE INCIDENCE OFFLASHOVER” by Johnson et al.

In one embodiment, the electrically conducive sealing surface 112 andthe insulating substrate 114, when assembled, form alongitudinally-oriented slot (not shown) defined therethrough forreciprocation of the knife blade. It is envisioned that knife channel(not shown) of jaw member 110 cooperates with a corresponding knifechannel 115 b defined in stationary jaw member 120 to facilitatelongitudinal extension of the knife blade along a preferred cuttingplane to effectively and accurately separate the tissue.

Jaw member 120 includes similar elements to jaw member 110 such as a jawhousing having an insulating substrate 124 and an electricallyconductive sealing surface 122 which is dimensioned to securely engagethe insulating substrate 124. Likewise, the electrically conductivesurface 122 and the insulating substrate 124, when assembled, include alongitudinally-oriented channel 115 a defined therethrough forreciprocation of the knife blade. As mentioned above, when the jawmembers 110 and 120 are closed about tissue, the knife channels of jawmembers 110, 120 form a complete knife channel to allow longitudinalextension of the knife blade in a distal fashion to sever tissue. It isalso envisioned that the knife channel may be completely disposed in oneof the two jaw members, e.g., jaw member 120, depending upon aparticular purpose.

As best seen in FIG. 2, jaw member 120 includes a series of stop members750 disposed on the inner facing surfaces of the electrically conductivesealing surface 122 to facilitate gripping and manipulation of tissueand to define a gap between opposing jaw members 110 and 120 duringsealing and cutting of tissue. It is envisioned that the series of stopmembers 750 may be employed on one or both jaw members 110 and 120depending upon a particular purpose or to achieve a desired result. Adetailed discussion of these and other envisioned stop members 750 aswell as various manufacturing and assembling processes for attachingand/or affixing the stop members 750 to the electrically conductivesealing surfaces 112, 122 are described in commonly-assigned, co-pendingU.S. Application Serial No. PCT/US01/11413 entitled “VESSEL SEALER ANDDIVIDER WITH NON-CONDUCTIVE STOP MEMBERS” by Dycus et al. which ishereby incorporated by reference in its entirety herein.

Jaw members 110 and/or 120 may be designed to be fixed to the end of atube 60 (see FIG. 2) extending from handle assembly 30 and configuredfor rotation about a longitudinal axis thereof. In this manner, rotationof tube 60 may impart rotation to jaw members 110 and/or 120 of endeffector assembly 100.

Turning now to FIGS. 3 and 4, an alternate embodiment of end effectorassembly 300, in accordance with the present disclosure, is shown andwill be described. It is envisioned that end effector assembly 300 mayinclude some, if not all, of the features and elements provided and/orassociated with end effector assembly 100.

As seen in FIGS. 3 and 4, end effector assembly 300 includes a centralshaft 302 supporting a pair of jaws 310, 320 at a distal end thereof ina unilateral arrangement. End effector assembly 300 includes a first orfixed jaw member 320 supported on a distal end 302 a of central shaft302, and a second or movable jaw member 310 pivotably supported atdistal end 302 a of central shaft 302 by a pivot pin 103. First andsecond jaw members 320, 310 are in juxtaposed relation to one anotherand are movable between an open condition, wherein tissue may bepositioned between jaw members 320, 310, and a closed configuration,wherein jaw members 320, 310 grasp and/or clamp onto tissue.

Jaw members 320, 310 are biased to the open condition by a biasingmember, e.g., spring, or the like (not shown),

End effector assembly 300 further includes an outer catheter sleeve 304defining a front or distal edge 304 a and a lumen 306 therethrough.Lumen 306 of outer sleeve 304 is configured and dimensioned totransiatably receive central shaft 302 and jaw members 320, 310 therein.

In operation, as central shaft 302 is withdrawn into outer sleeve 304,as indicated by arrow “A” in FIG. 4, distal edge 304 a of outer sleeve304 abuts against movable jaw member 310 and forces movable jaw member310 towards fixed jaw member 320. In so doing, tissue disposed betweenjaw members 310, 320 is clamped or grasped therebetween. It isunderstood that, in certain embodiments, that the greater the degree ofwithdrawal of central shaft 302 and jaw member 310, 320 into lumen 306of outer sleeve 304, the greater the clamping force exerted on thetissue disposed between jaw members 310, 320.

it is envisioned and within the scope of the present disclosure forcentral shaft 302 and/or outer sleeve 304 to be fabricated from aflexible material or the like. Central shaft 302 and/or outer sleeve 304may be fabricated from any one of or a combination of materialsincluding and not limited to, NITINOL (e.g., nickel-titanium alloys),polyurethane, polyester, and/or polymethylsiloxane material (PDMS),fluorinated ethylene-propylene (FEP), polytetrafluoroethylene (PTFE),nylon, etc.

Turning now to FIGS. 5 and 6, an end effector assembly, according toanother embodiment of the present disclosure, is generally designated as300 a. It is envisioned that end effector assembly 300 b may includesome, if not all, of the features and elements provided and/orassociated with end effector assembly 100.

End effector assembly 300 a includes a pair of jaw members 310 a, 320 aeach pivotably supported at a distal end of a central shaft 302 a via apivot pin 103. End effector assembly 300 a further includes an outercatheter sleeve 304 a defining a lumen 306 a therethrough. Lumen 306 aof outer sleeve 304 a is configured and dimensioned to translatablyreceive central shaft 302 a and jaw members 310 a, 320 a therein.

As seen in FIGS. 5 and 6, a linkage 330 or the like may be provided foractuating one of jaw members 310 a, 320 a relative to the other therebyeffectuating opening and closing of end effector assembly 300 a. Adistal end 330 a of linkage 330 is desirably connected to second jawmember 310 a at a location distal of pivot pin 103 when jaw members 310a, 320 a are disposed within outer sleeve 304 a. Linkage 330 isdesirably operatively connected to second jaw member 310 a in such amanner so as to effectuate rotation of second jaw member 310 a towardfirst jaw member 320 a upon movement of linkage 330 in a proximaldirection.

In use, with jaw members 310 a, 320 a in a closed condition, jaw members310 a, 320 a are advanced through lumen 306 a of outer sleeve 304, asindicated by arrow “B” of FIG. 5. After jaw members 310 a, 320 a havecleared the distal end or edge of outer sleeve 304 a (i.e., pivot pin103 has cleared or advanced beyond the distal end or edge of outersleeve 304 a), jaw members 310 a, 320 a may both be pivoted about pivotpin 103 to a substantially orthogonal orientation relative to centralshaft 302 a, as seen in FIG. 6. In order to pivot or rotate jaw members310 a, 320 a about pivot pin 103, linkage 330 is moved in a proximaldirection, as indicated by arrow “A”.

With jaw members 310 a, 320 a oriented in an orthogonal direction, jawmembers 310 a, 320 a may be opened and closed by moving linkage 330 in adistal or proximal direction. For example, by moving linkage 330 in adistal direction, second jaw member 310 a is rotated about pivot pin 103thereby spacing second jaw member 310 a from first jaw member 320 a. Inso doing, end effector assembly 300 a is configured to an open conditionand the tissue contacting surface of first jaw member 320 a is orientedapproximately 90° relative to a longitudinal axis of outer sleeve 304 a.With end effector assembly 300 a in an open condition, tissue may beplaced between jaw members 310 a, 320 a or jaw members 310 a, 320 a maybe placed over the tissue.

Following placement of tissue between jaw members 310 a, 320 a, linkage330 may be moved in a proximal direction thereby rotating second jawmember 310 a about pivot pin 103 to approximate second jaw member 310 atoward first jaw member 320 a. In so doing, end effector assembly 300 ais moved to a closed condition to grasp the tissue interposed betweenfirst and second jaw members 320 a, 310 a. Since jaw members 310 b, 320b are in an orthogonal configuration, retraction of linkage 330 in aproximal direction results in application of the clamping force in asubstantially linear direction relative to central shaft 302 b.

Following treatment of the tissue, linkage 330 may be reactuated torelease the treated tissue from between first and second jaw members 320a, 310 a. With the treated tissue released from between first and secondjaw members 320 a, 310 a, central shaft 302 a is withdrawn through outersleeve 304 a. In so doing, first and second jaw members 320 a, 310 a arere-oriented to an axially aligned orientation due to a camming actionbetween the distal edge of outer sleeve 304 a and first jaw member 320a.

It is envisioned and within the scope of the present disclosure forcentral shaft 302 a and/or outer sleeve 304 a to be fabricated from aflexible material or the like.

Turning now to FIGS. 7 and 8, an end effector assembly, according to analternate embodiment of the present disclosure, is generally shown as300 b. It is envisioned that end effector assembly 300 b may includesome, if not all, of the features and elements provided and/orassociated with end effector assembly 100.

As seen in FIGS. 7 and 8, end effector assembly 300 b includes a centralshaft 302 b supporting a pair of jaws 310 b, 320 b at a distal endthereof in a unilateral arrangement. End effector assembly 300 bincludes a first or fixed jaw member 320 b supported on a distal end ofcentral shaft 302 b, and a second or movable jaw member 310 b pivotablysupported at distal end of central shaft 302 b by a pivot pin 103. Firstand second jaw members 320 b, 310 b are in juxtaposed relation to oneanother and are movable between an open condition, wherein tissue may bepositioned between jaw members 320 b, 310 b, and a closed configuration,wherein jaw members 320 b, 310 b grasp and/or clamp onto tissue.

As seen in FIGS. 7 and 8, a linkage 330 b or the like may be providedfor actuating second jaw member 310 b relative to first jaw member 320b. A distal end 330 a of linkage 330 is desirably connected to secondjaw member 310. In particular, as seen in FIG. 7, distal end 330 a oflinkage 330 is connected to second jaw member 310 a in such a manner soas to effectuate rotation of second jaw member 310 b toward first jawmember 320 b upon movement of linkage 330 in a proximal direction, asindicated by arrow “A”, or away from first jaw member 320 b uponmovement of linkage 330 in a distal direction, as indicated by arrow“B”.

As disclosed above, it is envisioned and within the scope of the presentdisclosure that central shaft 302 b may be fabricated from a flexiblematerial or the like.

Turning now to FIGS. 9 and 10, an end effector assembly, according to afurther embodiment of the present disclosure, is generally designated as300 c. End effector assembly 300 c is substantially identical to endeffector assembly 300 b and will only be discussed in detail to theextent necessary to identify differences in construction and operation.

As seen in FIGS. 9 and 10, a central body portion 302 c of end effectorassembly 300 c includes a rigid distal portion 301 c and a flexibleproximal portion 303 c. Jaw members 310 c, 320 c are arranged in aunilateral configuration and are actuatable by any of the methodsdescribed above or known by one having skill in the art. Jaw members 310c, 320 c are desirably biased to an open condition by a biasing member,e.g., spring, or the like (not shown), or by the wire snare 340.

As seen in FIGS. 9 and 10, end effector assembly 300 c includes a wiresnare 340 extending out of one of jaw members 310 c, 320 c and anchoredto the other of jaw members 310 c, 320 c. In particular, wire snare 340is disposed within central body portion 302 c and includes a proximalend (not shown) which connects to an electrosurgical energy source, anda distal end 340 a that extends out through fixed jaw member 320 c andattaches to a distal end or tip of movable jaw member 310 c.

It is envisioned that wire 340 may be fabricated from a shape memoryalloy, such as, for example, NITINOL, or the like. Accordingly, as seenin FIG. 9, when end effector assembly 300 c is in the open condition,wire 340 has a substantially arcuate shape or configuration.

In use, in order to close end effector assembly 300 c, wire 340 iswithdrawn in a proximal direction thereby approximating the distal tipof movable jaw member 310 c toward the distal tip of fixed jaw member320 c. In so doing jaw members 310 c, 320 c are approximated toward oneanother and desirably clamp onto tissue “T”.

In one mode of operation, with end effector assembly 300 c in an opencondition and with wire 340 in an expanded condition, as seen in FIG. 9,end effector assembly 300 c is placed over tissue “T” to be excised,e.g., a polyp or the like, such that tissue “T” is interposed and/ordisposed within the space or area “S” defined between jaw members 310 c,320 c and wire 340. With tissue “T” positioned in space “S”, theproximal end of wire 340 is drawn in a proximal direction therebyclosing end effector assembly 300 c (e.g., approximating jaw members 310c, 320 c) onto tissue “T” and cinching wire 340 about tissue “T”.

Wire 340 is withdrawn an amount sufficient to tightly close end effectorassembly 300 c onto and/or about tissue “T” and to apply pressure totissue “T” between the jaw members 310 c, 320 c. At such a time,electrical current or electrical energy is transmitted through wire 340and/or to the electrically conducive sealing surface(s) of jaw members310 c, 320 c. The electrical current or energy is transmitted at a leveland for a time sufficient to heat wire 340 to cut through tissue “T” andremove tissue “T” from the underlying or remaining tissue.

It is envisioned that wire 340 may or may not be insulated.Additionally, distal portion 301 c of central shaft 300 c may befabricated from a rigid, electrically conductive material. In so doing,an electrical lead 311 c may extend through flexible proximal portion303 c of central shaft 302 c and electrically connect to a proximal endof rigid portion 301 c.

In another mode of operation, with end effector assembly 300 c in anopen condition and with wire 340 in an expanded condition, end effectorassembly 300 c is placed over tissue “T” to be excised, e.g., a polyp orthe like, such that tissue “T” is interposed and/or disposed between jawmembers 310 c, 320 c. With tissue “T” so positioned, the proximal end ofwire 340 is drawn in a proximal direction thereby cinching wire 340 andclosing end effector assembly 300 c (e.g., approximating jaw members 310c, 320 c) onto tissue “T”.

Wire 340 is withdrawn an amount sufficient to tightly close end effectorassembly 300 c onto tissue “T” and to apply pressure to tissue “T”between the jaw members 310 c, 320 c. It is envisioned that in thecurrent mode of operation, further withdrawal of wire 340 may result inpivoting of end effector assembly 300 c about pivot pin 103 to improvethe visibility at the surgical site.

Turning now to FIGS. 11 and 12, an end effector assembly, according to afurther embodiment of the present disclosure, is generally designated as300 d. End effector assembly 300 d is substantially identical to endeffector assembly 300 c and will only be discussed in detail to theextent necessary to identify differences in construction and operation.

As seen in FIGS. 11 and 12, end effector assembly 300 d includes a wire340 extending out of one of jaw members 310 d, 320 d and into the otherof jaw members 310 d, 320 d. In particular, wire 340 is disposed withincentral body portion 302 d and includes a proximal end (not shown) whichconnects to an electrosurgical energy source, and a distal end 340 awhich extends out through a distal tip of first jaw member 320 d andback into a distal tip of second jaw member 310 d. Distal end 340 a ofwire 340 is anchored or secured to itself according to any known method,including and not limited to use of a junction block 342. In thismanner, as will be described in greater detail below, withdrawal of wire340 in a proximal direction results in withdrawal of wire 340 throughboth jaw members 310 b, and 320 d.

While end effector assembly 300 d is shown as having bilateral jawmember arrangement, it is envisioned and within the scope of the presentdisclosure for end effector assembly 300 d to have a unilateral jawmember arrangement. It is envisioned that when end effector assembly 300d is in the open condition, wire 340 has a substantially arcuate shapeor configuration. Wire 340 includes a nipple region 340 b formed along alength thereof. In use, when cinching wire 340 it is desired for tissue“T” to be positioned within nipple region 340 b of wire 340.

In use, in order to close end effector assembly 300 d, wire 340 iswithdrawn in a proximal direction, by pulling on the proximal end ofwire 340, thereby approximating the distal tips of jaw members 310 d,320 d toward one another. Since distal end 340 a of wire 340 is securedto itself by junction block 342, by pulling on the proximal end of wire340, distal end 340 a of wire 340 is drawn into both jaw members 310 d,320 d substantially equally.

In operation, with end effector assembly 300 d in an open condition andwith wire 340 in an expanded condition, as seen in FIG. 11, end effectorassembly 300 d is placed over tissue “T” to be excised, e.g., a polyp orthe like, such that tissue “T” is interposed and/or disposed within thespace or area “S” defined between jaw members 310 d, 320 d and wire 340.With tissue “T” positioned in space “S”, the proximal end of wire 340 isdrawn in a proximal direction thereby closing end effector assembly 300d (e.g., approximating jaw members 310 d, 320 d simultaneously) ontotissue “T” and cinching wire 340 about tissue “T”.

Wire 340 is withdrawn an amount sufficient to tightly close end effectorassembly 300 d onto and/or about tissue “T” and to apply pressure totissue “T” between jaw members 310 d, 320 d. At such a time, electricalcurrent or electrical energy is transmitted through wire 340 and/or tothe electrically conducive sealing surface(s) of jaw members 310 d, 320d. The electrical current or energy is transmitted at a level and for atime sufficient to heat wire 340 to cut through tissue “T” and removetissue “T” from the underlying or remaining tissue.

In accordance with the present disclosure, the rigid nature of jawmembers 310, 320 provides greater support and/or control of wire 340 ascompared to conventional wire snare instruments and the like.

Turning now to FIGS. 13-17, an end effector assembly, according to afurther embodiment of the present disclosure, is generally designated as300 e. End effector assembly 300 e is substantially identical to endeffector assembly 300 c and will only be discussed in detail to theextent necessary to identify differences in construction and operation.

End effector assembly 300 e further includes a knife or scissor blade350 pivotably connected to a distal end of central shaft 302 e. Scissorblade 350 may be pivotably connected to the distal end of central shaft302 e via pivot pin 103. Scissor blade 350 defines a cutting edge 350 aor the like.

As seen in FIGS. 13-17, a linkage 352 or the like may be provided foractuating scissor blade 350 relative to jaw members 310 e, 320 e of endeffector assembly 300 e to sever tissue “T” and the like. A distal end352 a of linkage 352 is desirably connected to scissor blade 352 at alocation desirably distal of pivot pin 103. Linkage 352 is desirablyoperatively connected to scissor blade 350 in such a manner so as toeffectuate rotation of scissor blade 350 upon movement of linkage 352 ina proximal direction.

As seen in FIGS. 13 and 14, scissor blade 350 has a first position inwhich cutting edge 350 a thereof is in substantial registration with gap“G” between jaw members 310 e, 320 e, or, alternatively, cutting edge350 a of scissor blade 350 is in substantial registration with and/orsubstantially aligned with the sealing surface 122 e of jaw member 310e. As seen in FIGS. 15 and 16, scissor blade 350 has a second positionin which cutting edge 350 a thereof has been rotated past or beyond gap“G” between jaw members 310 e, 320 e, to thereby sever or cut tissue “T”extending from therebetween.

End effector assembly 300 e may further include a wire 340 extending outof one of jaw members 310 e, 320 e and anchored to the other of jawmembers 310 e, 320 e. In particular, wire 340 is disposed within centralbody portion 302 e and includes a proximal end (not shown) whichconnects to an electrosurgical energy source, and a distal end 340 awhich extends out through fixed jaw member 320 e and attaches to adistal end or tip of movable jaw member 310 e.

In operation, either prior to, during or following severing of tissue“T” with wire 340, as described above with regard to end effectorassemblies 300 c or 300 d, linkage 352 is actuated (e.g., moved in aproximal direction) to pivot scissor blade 350 about pivot pin 103 andsevering tissue “T” along the sides of jaw members 310 e, 320 e.

Desirably, scissor blade 350 has a length substantially equal to thelength of jaw members 310 e, 320 e. However, it is envisioned thatscissor blade 350 may have any length necessary or desired in order toperform the operative procedure.

It is envisioned and within the scope of the present disclosure for theproximal portions of any of the jaw members disclosed above and thedistal end of the respective central shafts to be covered by a resilientor flexible insulating material or boot (not shown) to reduce straycurrent concentrations during electrosurgical activation especially in amonopolar activation mode. As can be appreciated, when jaw members 310,320 are opened, the boot flexes or expands in certain areas in order toaccommodate the movement of jaw members 310, 320. Further detailsrelating to one envisioned insulating boot are described incommonly-owned and concurrently-filed U.S. Provisional PatentApplication Ser. No. 60/722,213, filed on Sept. 30, 2005, entitled“INSULATING BOOT FOR ELECTROSURGICAL FORCEPS”, the entire contents ofwhich being incorporated by reference herein.

Turning now to FIGS. 18-20, an end effector assembly, according to yetanother embodiment of the present disclosure, is generally designated as400. As seen in FIGS. 18-20, end effector assembly 400 includes acentral shaft 402 having a distal end 402 a configured and adapted tosupport a cutting blade 404 thereon. It is envisioned that central shaft402 may be either flexible or rigid along at least a portion of itslength.

Cutting blade 404 includes a cutting edge 404 a extending in asubstantially distal direction. Desirably, cutting edge 404 a of cuttingblade 404 lies along the central longitudinal axis of central shaft 402.

End effector assembly 400 includes a jaw member 406 movably associatedwith central shaft 402. In an embodiment, movable jaw member 406 isconfigured and adapted to translate longitudinally along and/or relativeto central shaft 402. Movable jaw member 406 includes a leg portion 406a extending substantially longitudinally along central shaft 402 and atissue contacting portion 406 b extending in a substantially orthogonaldirection from a distal end of leg portion 406 a. In particular, tissuecontacting portion 406 b of movable jaw member 406 extends across thecentral longitudinal axis of central shaft 402 and, more particularly,across cutting blade 404. Reference may be made to commonly-owned andconcurrently-filed U.S. Pat. No. 6,267,761; and U.S. patent applicationSer. No. 09/591,328, filed Jun. 9, 2000; and U.S. patent applicationSer. No. 11/170,616, filed on Jun. 29, 2005, the entire contents ofwhich being incorporated by reference herein, for exemplary embodimentsand modes of operation of end effector assembly 400.

Jaw member 406 is movable from a position in which tissue contactportion 406 b is spaced a distance from cutting edge 404 a of cuttingblade 404 to a position in which tissue contacting portion 406 b is incontact with cutting edge 404 a of cutting blade 404.

End effector assembly 400 further includes a floating anvil member 408interposed between cutting blade 404 and tissue contacting portion 406 bof jaw member 406. Anvil member 408 is slidably supported on leg portion406 a of jaw member 406 so that anvil member 408 is translatable alongleg portion 406 a. In one embodiment, anvil member 408 include a firstslot 408 a configured and dimensioned to slidably receive leg portion406 a of jaw member 406 therethrough. Anvil member 408 further includesa second or blade slot 408 b formed therein that is configured anddimensioned to permit reciprocal movement of cutting blade 404 into andout of blade slot 408 b (i.e., through anvil member 408).

End effector assembly 400 further includes a biasing member or spring410 interposed between cutting blade 404 and anvil member 408. Biasingmember 410 is configured so as to maintain anvil member 408 spaced adistance from cutting blade 404. Desirably, biasing member 408 maintainsanvil member 408 spaced from cutting blade 404 by an amount sufficientthat cutting edge 404 a of cutting blade 404 does not extend throughblade slot 408 b of anvil member 408.

It is envisioned that each of tissue contacting portion 406 b and anvilmember 408 may be electrically connected to an electrosurgical energysource (not shown) and are provided with elements (not shown) fordelivering and/or receiving electrosurgical energy.

With continued reference to FIGS. 18-20, an exemplary method of using asurgical instrument including an end effector assembly 400 is provided.As seen in FIG. 18, with jaw member 406 positioned such that tissuecontact portion 406 b is spaced a distance from anvil member 408, tissue“T” (e.g., a polyp or the like) in introduced therebetween, either byplacing end effector assembly 400 over tissue “T”, as shown, or bydrawing tissue “T” into the space therebetween.

As seen in FIG. 19, with tissue “T” interposed between tissue contactingportion 406 b of jaw member 406 and anvil member 408, jaw member 406 ismoved in a proximal direction relative to central shaft 402, asindicated by arrow “A”. In so doing, tissue “T” is clamped or graspedbetween tissue contacting portion 406 b of jaw member 406 and anvilmember 408. Desirably, a sufficient force is applied to jaw member 406so as to clamp tissue “T” between tissue contacting portion 406 bthereof and anvil member 408 and so as not to substantially move anvilmember 408 to compress biasing member 410. As discussed above, biasingmember 410 maintains anvil member 408 spaced a distance from cuttingblade 404 such that cutting edge 404 a does not extend beyond blade slot408 b.

With tissue “T” clamped between tissue contacting portion 406 b of jawmember 406 and anvil member 408, an effective amount of electrosurgicalenergy (e.g., for an effective time period at an effective energy level)is delivered to tissue contacting portion 406 b of jaw member 406 and/oranvil member 408 to achieve a desired effect in tissue “T”. Desirably,bipolar current is applied to seal the base of the tissue.

As seen in FIG. 20, with tissue “T” treated, jaw member 406 is furtheradvanced in a proximal direction, as indicated by arrow “A”, to overcomethe bias of biasing member 410 and advance anvil member 408 over cuttingblade 404. In so doing, cutting edge 404 a of cutting blade 404 severstissue “T” from the remaining underlying tissue.

In accordance with the present disclosure, any of the end effectorsdisclosed herein may be configured and adapted to deliver a workingpressure of about 3 kg/cm² to about 16 kg/cm² and, preferably, of about7 kg/cm² to about 13 kg/cm², to the tissue. By controlling theintensity, frequency and duration of the electrosurgical energy appliedto the tissue by the end effector assemblies, the user can cauterize,coagulate/desiccate, seal and/or simply reduce or slow bleeding.

From the foregoing and with reference to the various figure drawings,those skilled in the art will appreciate that certain modifications canalso be made to the present disclosure without departing from the scopeof the same.

It is also contemplated that the forceps 10 (and/or the electrosurgicalgenerator used in connection with the forceps 10) may include a sensoror feedback mechanism (not shown) that automatically selects theappropriate amount of electrosurgical energy to effectively seal theparticularly-sized tissue grasped between the jaw members. The sensor orfeedback mechanism may also measure the impedance across the tissueduring sealing and provide an indicator (visual and/or audible) that aneffective seal has been created between the jaw members. Examples ofsuch sensor systems are described in commonly-owned U.S. patentapplication Ser. No. 10/427,832 entitled “METHOD AND SYSTEM FORCONTROLLING OUTPUT OF RF MEDICAL GENERATOR”, the entire contents ofwhich being incorporated by reference herein.

It is envisioned that the outer surface of any of the end effectorassemblies disclosed herein may include a nickel-based material,coating, stamping, metal injection molding which is designed to reduceadhesion between the jaw members with the surrounding tissue duringactivation and sealing. Moreover, it is also contemplated that theconductive surfaces of the jaw members may be manufactured from one (ora combination of one or more) of the following materials: nickel-chrome,chromium nitride, MedCoat 2000 manufactured by The ElectrolizingCorporation of OHIO, inconel 600 and tin-nickel. The tissue conductivesurfaces may also be coated with one or more of the above materials toachieve the same result, i.e., a “non-stick surface”. As can beappreciated, reducing the amount that the tissue “sticks” during sealingimproves the overall efficacy of the instrument.

One particular class of materials disclosed herein has demonstratedsuperior non-stick properties and, in some instances, superior sealquality. For example, nitride coatings which include, but not are notlimited to: TiN, ZrN, TiAlN, and CrN are preferred materials used fornon-stick purposes. CrN has been found to be particularly useful fornon-stick purposes due to its overall surface properties and optimalperformance. Other classes of materials have also been found to reducingoverall sticking. For example, high nickel/chrome alloys with a Ni/Crratio of approximately 5:1 have been found to significantly reducesticking in bipolar instrumentation. One particularly useful non-stickmaterial in this class is Inconel 600. Bipolar instrumentation havingsealing surfaces 112 and 122 made from or coated with Ni200, Ni201(˜100% Ni) also showed improved non-stick performance over typicalbipolar stainless steel electrodes,

Any of the above-described endoscopic forceps and/or end effectorassemblies may be incorporated into a catheter-type configuration orother technology suitable for sealing/cutting, such as, for example,E-cutting technology (electrosurgical-cutting technology). Accordingly,any of the above-described endoscopic forceps and/or end effectorassemblies may be incorporated into systems, instruments, devices andthe like disclosed in U.S. patent application Ser. No. 11/418,876, filedon May 5, 2006, entitled “VESSEL SEALING INSTRUMENT WITH ELECTRICALCUTTING MECHANISM”; U.S. patent application Ser. No. 10/932,612, filedon Sept. 2, 2004, entitled “VESSEL SEALING INSTRUMENT WITH ELECTRICALCUTTING MECHANISM”; International Application Ser. No. PCT/US03/28539,filed on Sept. 11, 2003, entitled “ELECTRODE ASSEMBLY FOR SEALING ANDCUTTING TISSUE AND METHOD FOR PERFORMING SAME”, the entire contents ofeach of which is herein incorporated by reference.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Therefore, the abovedescription should not be construed as limiting, but merely asexemplifications of preferred embodiments. Those skilled in the art willenvision other modifications within the scope and spirit of the claimsappended hereto.

1. An endoscopic forceps for vessel sealing, comprising: a housing; ashaft extending from the housing and including a distal end configuredand adapted to support an end effector assembly; and an end effectorassembly operatively supported on the distal end of the shaft, the endeffector assembly including: a pair of jaw members movable from a firstposition in spaced relation relative to one another to at least a secondposition closer to one another for grasping tissue therebetween, each ofthe jaw members is adapted to connect to an electrosurgical energysource such that the pair of jaw members are capable of conductingenergy through tissue held therebetween to affect a tissue seal, whereinthe pair of jaw members are biased to the first position; and a wiresnare having a proximal end connectable to an electrosurgical energysource and a distal end translatably extending out of one of the pair ofjaw members and operatively associated with the other of the pair of jawmembers, wherein withdrawal of the proximal end of the wire snareresults in movement of the pair of jaw members from the first positionto the second position and a cinching of the wire snare.
 2. Theendoscopic forceps according to claim 1, wherein the pair of jaw membersoperate unilaterally.
 3. The endoscopic forceps according to claim 2,wherein the pair of jaw members operate bilaterally.
 4. The endoscopicforceps according to claim 2, wherein the distal end of the wire snaretranslatably extends through the other of the pair of jaw members and issecured to itself.
 5. The endoscopic forceps according to claim 4,wherein the wire snare is fabricated from a shape-memory alloy.
 6. Theendoscopic forceps according to claim 5, wherein at least a portion ofthe shaft is flexible.
 7. The endoscopic forceps according to claim 6,wherein a distal most end of the shaft is rigid.
 8. The endoscopicforceps according to claim 1, wherein the end effector assembly furtherincludes: a scissor blade operatively supported on a distal end of theshaft and movable from a first position in which the scissor blade issubstantially aligned with one of said pair of jaw members and aplurality of second positions in which the scissor blade is out ofalignment with the one of said pair of jaw members and extends across tothe other of the pair of jaw members thereby severing tissue graspedbetween the pair of jaw members.
 9. The endoscopic forceps according toclaim 8, wherein the end effector assembly further includes: a scissorblade linkage operatively connected to the scissor blade, whereinmovement of the scissor linkage results in actuation of the scissorblade between the first position and any number of the plurality ofsecond positions.
 10. An endoscopic forceps for vessel sealing,comprising: a housing; a shaft extending from the housing and includinga distal end configured and adapted to support an end effector assembly;an end effector assembly operatively supported on the distal end of theshaft, the end effector assembly including; a cutting blade supported onthe distal end of the shaft, the cutting blade including a cutting edgeextending in a distal direction; a movable jaw member translatablysupported on the shaft, the movable jaw member including a tissuecontacting portion extending across a longitudinal axis of the shaft;and an anvil member slidably supported on the movable jaw member betweenthe tissue contacting portion of the movable jaw member and the cuttingblade, the anvil member defining a blade slot formed therein forselectively receiving the cutting blade therethrough; and a movablehandle operatively associated with the housing, wherein actuation of themovable handle relative to the housing results in movement of themovable jaw member relative to the shaft.
 11. The endoscopic forcepsaccording to claim 10, wherein the end effector assembly furtherincludes a biasing member disposed between the anvil member and thecutting blade for maintaining the anvil member biased a distance awayfrom the cutting blade such that the cutting blade does not extendthrough the anvil member.
 12. The endoscopic forceps according to claim11, wherein the end effector assembly includes: a first position whereinthe tissue contacting portion of the movable jaw member is spaced adistance from the anvil member for receiving a target tissue therein,and the anvil member is spaced a distance from the cutting blade suchthat the cutting blade does not extend through the blade slot formedtherein; a second position wherein the tissue contacting portion of themovable jaw member is approximated toward the anvil member to grasp thetissue therebetween, and the anvil member is spaced a distance from thecutting blade such that the cutting blade does not extend through theblade slot formed therein; and a third position wherein the tissuecontacting portion of the movable jaw member is approximated toward theanvil member to grasp the tissue therebetween, and the anvil member isapproximated toward the cutting blade such that the cutting edge of thecutting blade extends through the blade slot formed therein severs thetissue extending thereacross.
 13. An endoscopic forceps for vesselsealing, comprising; a housing; a shaft extending from the housing andincluding a distal end configured and adapted to support an end effectorassembly; and an end effector assembly operatively supported on thedistal end of the shaft, the end effector assembly including; a fixedjaw member and a movable jaw member, movable relative to the fixed jawmember, from a first position in spaced relation relative to one anotherto at least a second position closer to one another for grasping tissuetherebetween, each of the jaw members is adapted to connect to anelectrosurgical energy source such that the jaw members are capable ofconducting energy through tissue held therebetween to affect a tissueseal, wherein the jaw members are biased to the first position; and awire snare having a proximal end connectable to an electrosurgicalenergy source and a distal end translatably extending out of the fixedjaw and operatively associated with the movable jaw member, whereinwithdrawal of the proximal end of the wire snare results in movement ofthe jaw members from the first position to the second position and acinching of the wire snare.
 14. The endoscopic forceps according toclaim 13, wherein the distal end of the wire snare translatably extendsthrough the movable jaw member and is secured to itself.
 15. Theendoscopic forceps according to claim 14, wherein the wire snare isfabricated from a shape-memory alloy.
 16. The endoscopic forcepsaccording to claim 15, wherein at least a portion of the shaft isflexible.
 17. The endoscopic forceps according to claim 13, wherein theend effector assembly further includes: a scissor blade operativelysupported on a distal end of the shaft and movable from a first positionin which the scissor blade is substantially aligned with the movable jawmember and a plurality of second positions in which the scissor blade isout of alignment with the movable jaw member and extends across to thefixed jaw member thereby severing tissue grasped between the fixed andmovable jaw members.
 18. The endoscopic forceps according to claim 17,wherein the end effector assembly further includes: a scissor bladelinkage operatively connected to the scissor blade, wherein movement ofthe scissor linkage results in actuation of the scissor blade betweenthe first position and any number of the plurality of second positions.